Textile sliver evening apparatus



United States Patent 3,403,426 TEXTiLE SLIVER EVENING APPARATUS Erhard Edwin Stiepel, and Joseph Brown Wallace, Clemson, S.C., assignors to Maremont Corporation, Chicago, 111., a corporation of Illinois Fiied July 27, 1966, Ser. No. 568,260 8 Claims. (Cl. 19240) ABSTRACT OF THE DISCLOSURE Textile drafting apparatus for reducing or eliminating mass variations in laminated ribbon staple fiber sliver which includes two pairs of successive evener rolls providing short term speed variations, the first pair of rolls being a tongue and groove roll set, one of which rolls moves away from the other in response to the sliver mass which movement is sensed to vary the speed of the second pair of rolls, the first pair of rolls being driven at a constant speed and photocell sensing means for sensing a predetermined loop size of the ribbon sliver after the ribbon sliver leaves the second pair of rolls, and drafting element drive means responsive to the quantity sensing means to vary the speed of said drafting element drive means to maintain the predetermined quantity providing a delivery of evened drafted sliver having long term speed variations.

This invention relates to textile drafting apparatus for reducing mass variations in staple fiber sliver, especially in apparatus in which staple fiber sliver is continuously delivered from a battery of cards or the like to a high speed draw frame.

Modern automated staple fiber handling systems are capable of continuously producing and drafting a sliver at high speed, with deliveries of the order of 1200 to 1600 feet a minute. Such systems, in addition to a bale opener if baled staple fiber is used, commonly employ a battery of four to eight cards or the like, preferably to produce a laminated sliver in ribbon form which is continuously drafted by a high speed draw frame. It has been found to be important in such a system immediately to draft the laminated sliver upon its delivery from the multiple cards, without intervening packaging, not only because the laminated ribbon sliver tends to separate if it not be drafted to combine and blend it into a unitary sliver, but also because by drafting it in the same direction of advance as that of its advance through the cards, the fiber hooks produced by the latter are much reduced, producing a superior sliver for subsequent spinning.

However, with a system such as that described above, though it has been known to be desirable, it has not been considered to be possible to provide for sliver evening to reduce or eliminate mass variations in the laminated ribbon staple fiber sliver by varying the relative speed of the draw frame rolls in response an appropriate sensor for the instantaneous mass of the sliver. This is because the inertia of the draw frame rolls and their driving mechanisms in a high speed draw frame, that is, one capable of sliver output speeds of 1200 to 1600 feet per minute and beyond, is so great as to make it impractical to deal with relatively short term mass variations, by varying draw frame roll speed, although long term variations can so be taken care of.

Accordingly, it is a major object of the present invention to provide, in a system having continuous and direct sliver delivery to a draw frame, sliver evening capable of dealing with relatively short term sliver mass variations, as well as long term variations.

This we have accomplished in a novel manner by providing, in advance of the draw frame, a sliver evening device, capable of dealing with relatively short term sliver ice mass variations but delivering sliver at rates of speed varying in proportion to said mass variations, in combination with sliver delivery rate integrating means positioned between the evening device and the draw frame, and means for varying the draw frame speed in response to a signal from the integraing means. Such sliver delivery rate integrating means, according to the invention, is effective to establish and maintain a stored quantity of sliver, preferably in the form of a loop of predetermined size, which in effect converts the relatively short term rate variations from the sliver evener device into long term variations in sliver rate which can be accommodated by relatively slow draw frame speed variations. The stored quantity of sliver, and hence its long term rate variations, may be sensed by appropriate sensing means such as a photocell system to which the draw frame drive is responsive to vary the speed of the draw frame in response to loop size and so accommodate such long term variations.

For the purpose of explaining further features and objects of the present invention, reference is now made to the following detailed description of a preferred embodiment thereof, taken together with the accompanying drawing, wherein is shown a somewhat diagrammatic, isometric view of a system according to the present invention.

In the drawing is shown textile drafting apparatus according to the invention including four cotton cards 12, 14, 16, 18 or other sliver supply apparatus, continuously and directly supplying a composite sliver S to a high speed draw frame, generally designated 20, for drafting and delivery of a unitary blended sliver through its calender rolls 21 for coiling in a can 26. Suitable common drive means including a shaft 27 are provided for driving all the cards from motor 28 to produce a composite sliver at a constant predetermined rate of speed, although other types of synchronous drive systems could be used. Preferably, the cards or the like are each constructed and arranged to produce a fiat ribbon sliver, with such slivers being combined by appropriate turning bars 13, 15, 17, 19 for movement along sliver table 11 in laminated form with their edges aligned. Such formation and arrangement of a composite flat sliver is fully described in application for US. Patent, Ser. No. 555,561, filed June 6, 1966 having a common assignor, and need not further be described herein.

Draw frame 20 includes a drafting element having -a plurality of pairs of rolls 22, 23, 24 driven at successively higher speed to provide a draft of about 5 to 10 with the combined and blended unitary ribbon sliver being delivered therefrom by its calender rolls 21 at about 1200 to 1600 feet a minute. Its rolls are all driven by motor 28 through a variable speed drive 25 having a manual control 29 and an automatic control hereinafter described. Draw frame 20 and its associated means for coiling the combined unitary sliver into can 26 are well known to the art and so also need not be described herein, except as to their association with the additional elements of the present invention, all as hereinafter described.

The sliver evener device, as preferably utilized in the present invention, consists of two pairs of variable draft drafting rolls, having a draft ratio variable between about 1.1 and 2.1, with a mean draft of about 1.6. The rear pair of rolls is a tongue and groove roll set with one of said rolls having a groove about its periphery of the same width as that of the ribbon sliver presented to it. Of the set, upper roll 32 cooperates with the groove of lower roll 30 by fitting closely within it, such upper roll being arranged to sense the instantaneous mass of sliver passing thereby by reason of its pivotal mounting by arms 34 on shaft 36 connected to shaft angle sensor 38. Lower roll 36 is driven from motor 28 to provide a uniform peripheral speed of the rear rolls 30, 32 the same as that of the delivery speed of the cards 12, 14, 16, 18 and the laminated sliver produced thereby. The front pair of the evener rolls includes lower roll 40 and upper roll 42, such rolls being driven by motor 28 through a variable speed drive 44, controlled by the angular position of sensor shaft 36 responsive to the instantaneous mass of sliver passing between rear rolls 30 and 32. Other types of sliver evener sensing means, such as those utilizing light, electrical capacitance, beta rays or sound absorption may be utilized.

The operation of such an evener is well known in the art, in that the speed of the front set of rolls is varied in response to the mass variations sensed by the rear set of rolls or otherwise to vary the draft applied to the sliver and so even it as it passes through the drafting zone between the pair of rolls to provide an evened sliver either free from or having much reduced mass variations. Unfortunately, however, as a necessary concomitant of such evening, there results a variable speed delivery which has, before the present invention, made it impossible effectively to use such an evener in conjunction with a modern high speed draw frame.

In order to make it possible to feed the evened sliver delivered at a variable rate from the evener device directly to such a high speed draw frame without interven ing packaging, the present invention provides novel sliver delivery rate integrating means which, in effect, converts the short term sliver delivery rate variations from the evener device into long term variations which can be accommodated by relatively slow, long term, speed changes of the draw frame responsive to such long term variations. Preferably, this is accomplished by establishing and maintaining, between the evener device and the drafting rolls of the draw frame, a quantity of sliver in the form of a loop L of predetermined size. As shown in the drawing, the loop L is so maintained by loop size sensing means consisting of four vertically spaced photocells 51, 53, 55, 57 and their cooperating individual light sources 52, 54, 56, 58, respectively, the photocells being electrically connected to the draw frame variable speed drive 25 to control it. As shown, the photocells and their light sources may be mounted, respectively, on opposite side walls 62, 64 of a trough-like loop enclosure having a bottom Wall 63 in vertically spaced position for their light beams (shown as dotted lines in the drawing) successively to be interrupted by a loop of ribbon sliver maintained between evener output rolls 40, 42 and draw frame input rolls 22.

In operation, the laminated ribbon sliver is continuously delivered at a uniform speed to the sliver evener rear rolls 30, 32 rotated at the same speed by common driving motor 28. At the rear rolls, the instantaneous mass of the ribbon sliver is sensed as it passes through the groove of lower roll 30 between said lower roll and upper roll 32 riding in said groove and pressing the sliver passing between the rolls, the upper roll being free to move in a direction toward and away from the lower roll but normally being urged toward the lower roll as by gravity, or spring, fluid or magnetic forces or the like. By reason of the mounting of upper roll 32 by arms 34 on sensor shaft 36, such movement of upper rolls 32 rotates shaft 36 in response to instantaneous variations in the sliver mass for control of the variable speed drive 44 of the evener output rolls 40, 42 to even the sliver by varying the draft in the drafting zone defined between the pairs of evener rolls. The variations in speed of the evener output rolls necessarily produces variations in the speed at which sliver is delivered from them, and such variations may and frequently do occur over a relatively short term.

By reason of the novel short term rate integrating function of the apparatus of the present invention, the relatively short term variations in the evener delivery rate are converted into long term variations which can be absorbed by relatively slowly occurring variations in the speed of the high speed draw frame, the inertia of the rotating elements of which is so high that speed changes to accommodate short term rate variations is entirely impractical. Thus, a quantity of sliver in the form of a loop L of predetermined size is established and maintained between the evener device and the draw frame by means of the photocell sensors and the draw frame variable speed drive.

More specifically, as shown in the drawing, the predetermined loop size is defined as a loop L having its lower end positioned in the region between the two intermediate photocell sensors 53, 55. The draw frame speed, by means of its variable speed drive manual controller 29, can be set to an average speed that will tend to maintain the sliver loop L in such position. In the event, however, that sliver mass variations are such that a higher than average evener delivery rate occurs, the loop end will move to a lower position and interrupt the beam between photocell 53 and its light source 54. This in turn will act through variable speed drive 25 to increase the speed of draw frame 20 and so move the loop end upwardly until the beam is no longer interrupted. Photocell 51 and its light source 52 function in the same manner, but provide a further speed increase of the drafting roll speeds in order to accommodate any possible extreme changes in predetermined loop size. Movement of the loop end upwardly, successively to expose the beams between photocell 55 and its source 56 and photocell 57 and its source 58, will produce drive frame speed changes in the opposite sense, to slow the draw frame from its normal speed, until the loop is once more restored to its predetermined size.

Although a photocell sensing system is herein described, it will be understood that other means, such as for example a scale, may be utilized to define the predetermined quantity of sliver that must be established and maintained between the evener device and the high speed draw frame according to the invention.

Except for the relatively slow speed long term rate changes of draw frame 20 as provided by its variable speed drive 25, its operation, and that of its associated calender rolls and coiler, if used, are entirely conventional, insofar as the present invention is concerned, but, otherwise, the invention for the first time makes it possible to provide sliver evening with a high speed draw frame to which is delivered a laminated sliver continuously and uniformly fed from multiple staple fiber deliveries, such as a card, comber, or filament cutter.

Still other modifications, within the spirit of the invention and the scope of the appended claims will occur to those skilled in the art.

What is claimed is:

1. In textile sliver drafting apparatus for reducing mass variations in staple fiber sliver having:

sliver evener means producing an evened sliver de livery having short term speed variations and sliver drafting means including a drafting element, sliver delivery rate integrating means establishing and maintaining a predetermined quantity of sliver between said sliver evener means and said sliver drafting means including quantity sensing means and drafting element variable speed drive means said drafting element drive means being responsive to said quantity sensing means to vary the speed of said drafting element drive means to maintain said predetermined quantity providing a delivery of evened drafted sliver having long term speed variations.

2. Textile sliver drafting apparatus as claimed in claim 1 further including loop size sensing means for sensing said sliver quantity in the form of a loop of predetermined size.

3. Textile sliver drafting apparatus as claimed in claim 2 wherein:

said loop size sensing means includes photocell sensing means for sensing predetermined maximum and minimum loop sizes. 4. Textile sliver drafting apparatus for reducing mass variations in staple fiber sliver comprising:

sliver supply means supply drive means for driving said sliver supply means at a predetermined uniform speed sliver evener means receiving sliver from said supply means at said predetermined uniform speed and providing an evened sliver delivery having short term speed variations sliver drafting means including a drafting element and drafting element variable speed drive means and sliver delivery rate integrating means establishing and maintaining a predetermined quantity of sliver between said sliver evener means and said sliver drafting means including quantity sensing means said drafting element drive means being responsive to said quantity sensing means to vary the speed of said drafting element drive means to maintain said predetermined quantity providing a delivery of evened draft sliver having long term speed variations. 5. Textile sliver drafting apparatus as claimed in claim 4 wherein said sliver evener means comprises two pairs of successive evener rolls providing an evening drafting zone therebetween at least one of said rolls of said first pair functioning as a sliver mass sensing means for sensing the mass of said sliver adjacent to and in advance of said evening drafting zone and drive means driving the first pair of said evener rolls at said constant speed and the second pair of said evener rolls at a speed responsive to said sensing means for evening said sliver. 6. Textile sliver drafting apparatus as claimed in claim 5 wherein:

the first of said pairs of evener rolls is a tongue and groove roll set mounted for movement toward and away from one another in response to the sliver mass. 7. Textile sliver drafting apparatus as claimed in claim 6 wherein:

said sliver evener means produces a ribbon sliver having a predetermined width corresponding to the width of the groove of said tongue and groove rolls.

8. Textile sliver drafting apparatus for reducing mass variations in staple fiber sliver comprising:

sliver supply means supply drive means for driving said sliver supply means at a predetermined uniform speed sliver evener means receiving sliver from said supply means at said predetermined uniform speed and providing an evened sliver delivery having short term speed variations sliver drafting means including a drafting element having a draft of at least about 5 to 10 and drafting element variable speed drive means and sliver delivery rate integrating means establishing and maintaining a quantity of sliver in the form of a loop of predetermined size between said sliver evener means and said sliver drafting means including loop size sensing means comprising photocell sensing means for sensing said predetermined loop size said drafting element drive means being responsive to said loop size sensing means to vary the speed of said drafting element drive means to maintain said loop at said predetermined size, providing a delivery of evened drafted sliver having long term speed variations.

References Cited UNITED STATES PATENTS 802,492 10/1905 Birch 19-240 3,184,798 5/1965 Burnet el al. 19-106 XR MERVIN STEIN, Primary Examiner.

D. NEWTON, Assistant Examiner. 

